RE: ACTION ITEM: second rework of general section about extending/customizing schemas (http://www.w3.org/International/its/track/actions/1)

Hi Felix,

I am fine to go for your material for 4. and 5. I didn't use it initially,
since I was under the impression that we might have to go for something
shorter.

Cheers,
Christian

-----Original Message-----
From: Felix Sasaki [mailto:fsasaki@w3.org] 
Sent: Freitag, 28. September 2007 14:30
To: Lieske, Christian
Cc: public-i18n-its@w3.org
Subject: Re: ACTION ITEM: second rework of general section about
extending/customizing schemas
(http://www.w3.org/International/its/track/actions/1)

Hi Christian,

I'm fine with the NEW additions. Just some more comments below.

Lieske, Christian wrote:
> Hi there,
>
> Here's a second modified version of the draft (see the "NEW>" stuff). The
modifications should address
> the input from Felix and Jirka. Please note, that we still need to find
the material
> for the "additional references".
>   

sorry, not here yet.

> Cheers,
> Christian
> ===
>
> The "How to do this" parts of this document often contain statements
related
> to schema creation or modification. The statements pertain to one of the
> following state-of-affairs:
>
> 1. creating a new schema
> 2. modifying an existing schema 
>
> The following aspects may need to be taken into account when working on
both
> of these topics:
>
> 1. Think twice before creating your own schema. Consider strongly existing
> formats such as DITA, DocBook, Open Document Format, Office Open XML,
> XML User Interface Language, Universal Business Language, ... Those
formats 
> have many insights 'built-in'.
>
> 2. The format itself should be carefully
> checked with regard to modification capabilities. DocBook and DITA for
> example come with their own set of features for adapting them to a special
> need.
>
> 3. The mechanisms which you can or have to use depend on the schema
> language (DTD, XSD, RelaxNG, ...). Namespace-based modularization of
schemas
> for example is difficult to realize for DTDs.
>
> NEW> NVDL, which can amongst others be viewed as a meta-schema language, 
> NEW> enables approaches which may be hard to realize otherwise.
>
> 4. Each schema language provides ways of extending or modifying existing
> schemas. XSD for example provides statements such as "import",
> "include", or "redefine" as well as mechanisms such as type
> substitution/derivation.
>   
I still would prefer my version of 4 described at 
http://lists.w3.org/Archives/Public/public-i18n-its/2007JulSep/0095.html ;)

> 5. Some processors do not implement support for all schema language
> constructs.
> Thus, a schema which works in one environment may not work in a different
> one.
>
>   
same for 5.

Cheers,

Felix